About: Temperature coefficient is a(n) research topic. Over the lifetime, 14126 publication(s) have been published within this topic receiving 202714 citation(s).
TL;DR: The extremely high value of the thermal conductivity suggests that graphene can outperform carbon nanotubes in heat conduction and establishes graphene as an excellent material for thermal management.
Abstract: We report the measurement of the thermal conductivity of a suspended single-layer graphene. The room temperature values of the thermal conductivity in the range ∼(4.84 ± 0.44) × 103 to (5.30 ± 0.48) × 103 W/mK were extracted for a single-layer graphene from the dependence of the Raman G peak frequency on the excitation laser power and independently measured G peak temperature coefficient. The extremely high value of the thermal conductivity suggests that graphene can outperform carbon nanotubes in heat conduction. The superb thermal conduction property of graphene is beneficial for the proposed electronic applications and establishes graphene as an excellent material for thermal management.
Abstract: A new compound composed of Nd, Fe, and a small quantity of B (about 1 wt. %) has been found, which has a tetragonal structure with lattice constants a=0.880 nm and c=1.221 nm. This phase, which has the approximate composition, 12 at. % Nd, 6 at. % B and balance Fe, possesses remarkable magnetic properties. From the approach to saturation an anisotroy constant of about 3.5 MJ/m3 can be calculated, while saturation magnetization amounts to 1.35 T. The magnetization versus temperature curve shows a Curie temperature of 585 K, which is much higher than those of the Fe and light rare earth binary compounds. Based on the new compound, sintered permanent magnets have been developed which have a record high energy product. Permanent magnet properties and physical properties of a typical specimen which has the composition Nd15B8Fe77 are as follows: Br =1.23 T, HcB =880 kA/m, HcI =960 kA/m, (BH)max =290 kJ/m3, temperature coefficient of Br =−1260 ppm/K, density=7.4 Mg/m3, specific resistivity=1.4 μΩm, Vickers hardn...
Abstract: Electroceramics are advanced materials whose properties and applications depend on the close control of structure, composition, ceramic texture, dopants and dopant (or defect) distribution. Impedance spectroscopy is a powerful technique for unravelling the complexities of such materials, which functions by utilizing the different frequency dependences of the constituent components for their separation. Thus, electrical inhomogeneities in ceramic electrolytes, electrode/electrolyte interfaces, surface layers on glasses, ferroelectricity, positive temperature coefficient of resistance behavior and even ferrimagnetism can all be probed, successfully, using this technique.
••01 Jan 1976
Abstract: A positive temperature coefficient is the term which has been used to indicate that an increase in solubility occurs as the temperature is raised, whereas a negative coefficient indicates a decrease in solubility with rise in temperature.
TL;DR: The investigated the temperature dependence of the frequency of G peak in the Raman spectra of graphene on Si/SiO2 substrates to shed light on the anharmonic properties of graphene.
Abstract: We investigated the temperature dependence of the frequency of G peak in the Raman spectra of graphene on Si/SiO2 substrates. The micro-Raman spectroscopy was carried out under the 488 nm laser excitation over the temperature range from -190 to +100 degrees C. The extracted value of the temperature coefficient of G mode of graphene is chi = -0.016 cm-1/ degrees C for the single layer and chi = -0.015 cm-1/ degrees C for the bilayer. The obtained results shed light on the anharmonic properties of graphene.